I bought my first knife last June. I have now spent over $3,500.

However, a very generous friend gave me a custom by maker D.F. Kressler, so I
have $8,500 of knives.
I am 13, and I get my knife money by petsitting.
Boy, I guess knife collecting is expensive. They didn't tell me that I would become addicted when I bought my first Kershaw for $25.
But, I guess my other hobbies are expensive too. For instance, I spent about $1,000 in
upgrades for a $350 RC car to make it go 83 MPH, and in mid and high power rocketry, you pay $20 to $40 per flight, not counting the $100+ rockets.